Rapid determination of an antenna pattern

ABSTRACT

An electronic device that determines one or more antenna patterns is described. During operation, this electronic device may reserve N time slots in a communication channel. Then, the electronic device may provide predefined frames in the N time slots that are intended for the second electronic device, where each time slot is associated with a different antenna pattern of an antenna. For example, the predefined frames may include null data packets (NDPs), and the time slot may have an extremum value of a performance metric, such as a signal-to-noise ratio. Moreover, the electronic device may receive feedback associated with the second electronic device, where the feedback includes information specifying at least a time slot in the N time slots. Next, the electronic device may select, based at least in part on the feedback, an antenna pattern associated with the time slot for use when communicating with the second electronic device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent Ser. No. 16/290,218,“Rapid Determination of an Antenna Pattern,” by Shuai Xiao, filed onMar. 1, 2019, the contents of which are herein incorporated byreference.

BACKGROUND Field

The described embodiments relate to techniques for determining one ormore antenna patterns.

Related Art

Many electronic devices are capable of wirelessly communicating withother electronic devices. For example, these electronic devices caninclude a networking subsystem that implements a network interface for:a cellular network (UMTS, LTE, etc.), a wireless local area network,e.g., a wireless network such as described in the Institute ofElectrical and Electronics Engineers (IEEE) 802.11 standard (which issometimes referred to as ‘Wi-Fi’, from the Wi-Fi Alliance of Austin,Tex.), Bluetooth™ (from the Bluetooth Special Interest Group ofKirkland, Wash.), and/or another type of wireless network.

During Wi-Fi communication, there may be crosstalk or interference fromother electronic devices in proximity. In addition, in a dynamiccommunication environment, the communication path between electronicdevices may vary as a function of time. In order to address theseproblems, some access points use electronic-device-specific antennapatterns during transmit and/or receive.

However, it can be difficult and time consuming to determine theappropriate antenna pattern to use during communication with aparticular electronic device. Moreover, existing approaches fordetermining an antenna pattern often involve back-and-forthcommunication (e.g., the exchange of multiple packets or frames) betweenan access points and associated electronic devices in a wireless localarea network (WLAN). This can increase the overhead in the WLAN.Consequently, the difficulties in determining antenna patterns candegrade the performance during Wi-Fi communication.

SUMMARY

An electronic device that determines an antenna pattern is described.This electronic device may include an antenna and an interface circuitthat wirelessly communicates with a second electronic device. Duringoperation, the electronic device may reserve N time slots in acommunication channel. Then, the electronic device may provide, from theinterface circuit, predefined packets or frames in the N time slots thatare intended for at least the second electronic device, where each timeslot is associated with a different antenna pattern of the antenna.Moreover, the electronic device may receive, at the interface circuit,feedback associated with the second electronic device, where thefeedback includes information specifying at least a time slot in the Ntime slots. Next, the electronic device may select, based at least inpart on the feedback, the antenna pattern associated with the time slotfor use when communicating with the second electronic device.

Note that the N time slots may be consecutive.

Moreover, the predefined packets or frames may include null data packets(NDPs).

Furthermore, the time slot may have an extremum value of a performancemetric. For example, the performance metric may include asignal-to-noise ratio.

Additionally, the information may specify a set of ranked time slots.For example, the set of time slots may be ranked based at least in parton performance metrics associated with the time slots, where a givenperformance metric may include: a signal-to-noise ratio, an angle ofarrival or both.

In some embodiments, the feedback includes a feedback frame.

Note that the electronic device may include an access point.

Moreover, the interface circuit may wirelessly communicate with a thirdelectronic device. Then, during operation, the electronic device may:receive, at the interface circuit, second feedback associated with thethird electronic device, where the second feedback comprises informationspecifying at least a second time slot in the N time slots; and select,based at least in part on the second feedback, a second antenna patternassociated with the second time slot for use when communicating with thethird electronic device.

Note that the feedback and the second feedback may include differentfeedback frames. Alternatively or additionally, the feedback and thesecond feedback may be conveyed in different sub-channels in a feedbackframe.

Furthermore, the electronic device may serially provide, from theinterface circuit, polling information intended for the secondelectronic device and second polling information intended for the thirdelectronic device. Alternatively, the electronic device may provide,from the interface circuit, a trigger frame intended for the secondelectronic device and the third electronic device, where the feedbackand the second feedback are received concurrently in differentsub-channels in a feedback frame.

In some embodiments, the electronic device may select, based at least inpart on the feedback and the second feedback, a common antenna patternfor use when communicating jointly with the second electronic device andthe third electronic device.

Another embodiment provides a computer-readable storage medium for usewith the electronic device. This computer-readable storage medium mayinclude program instructions that, when executed by the electronicdevice, cause the electronic device to perform at least some of theaforementioned operations.

Another embodiment provides a method for determining an antenna pattern.This method includes at least some of the operations performed by theelectronic device.

This Summary is provided for purposes of illustrating some exemplaryembodiments, so as to provide a basic understanding of some aspects ofthe subject matter described herein. Accordingly, it will be appreciatedthat the above-described features are examples and should not beconstrued to narrow the scope or spirit of the subject matter describedherein in any way. Other features, aspects, and advantages of thesubject matter described herein will become apparent from the followingDetailed Description, Figures, and Claims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram illustrating an example of a system inaccordance with an embodiment of the present disclosure.

FIG. 2 is a flow diagram illustrating an example method for determiningan antenna pattern in the system in FIG. 1 in accordance with anembodiment of the present disclosure.

FIG. 3 is a drawing illustrating an example of communication amongelectronic devices in FIG. 1 in accordance with an embodiment of thepresent disclosure.

FIG. 4 is a timing diagram illustrating an example of communicationamong electronic devices in FIG. 1 in accordance with an embodiment ofthe present disclosure.

FIG. 5 is a drawing illustrating an example of an antenna pattern of anantenna in one of the electronic devices in the system in FIG. 1 inaccordance with an embodiment of the present disclosure.

FIG. 6 is a flow diagram illustrating an example method for determiningan antenna pattern in the system in FIG. 1 in accordance with anembodiment of the present disclosure.

FIG. 7 is a drawing illustrating an example of communication amongelectronic devices in FIG. 1 in accordance with an embodiment of thepresent disclosure.

FIG. 8 is a timing diagram illustrating an example of communicationamong electronic devices in FIG. 1 in accordance with an embodiment ofthe present disclosure.

FIG. 9 is a block diagram illustrating an example of an electronicdevice in accordance with an embodiment of the present disclosure.

Note that like reference numerals refer to corresponding partsthroughout the drawings. Moreover, multiple instances of the same partare designated by a common prefix separated from an instance number by adash.

DETAILED DESCRIPTION

An electronic device that determines one or more antenna patterns isdescribed. During operation, this electronic device may reserve N timeslots in a communication channel. Then, the electronic device mayprovide predefined packets or frames in the N time slots that areintended for at least the second electronic device, where each time slotis associated with a different antenna pattern of an antenna. Forexample, the predefined packets or frames may include null data packets(NDPs), and the time slot may have an extremum value of a performancemetric, such as a signal-to-noise ratio. Moreover, the electronic devicemay receive feedback associated with the second electronic device, wherethe feedback includes information specifying at least a time slot in theN time slots. Next, the electronic device may select, based at least inpart on the feedback, an antenna pattern associated with the time slotfor use when communicating with the second electronic device.

In some embodiments, the electronic device may receive second feedbackassociated with a third electronic device, where the second feedbackincludes information specifying at least a second time slot in the Ntime slots. Then, based at least in part on the second feedback, theelectronic device selects a second antenna pattern associated with thesecond time slot for use when communicating with the third electronicdevice. Alternatively or additionally, the electronic device may select,based at least in part on the feedback and the second feedback, a commonantenna pattern for use when communicating jointly with the secondelectronic device and the third electronic device.

By using the predefined packets or frames in the N time slots to rapidlyprobe the performance of different antenna patterns, this communicationtechnique may improve the communication performance of the electronicdevice. For example, the communication technique may reduce the time andthe communication overhead needed to determine the one or more antennapatterns. In some embodiments, the one or more antenna patterns may bedetermined in, e.g., 5× less time than in other approaches (such asthose based on throughput). Moreover, the communication technique mayreduce crosstalk or interference when the electronic device communicateswith one or more electronic devices, such as the second electronicdevice and/or the third electronic device. Consequently, thecommunication technique may improve the user experience, and thus mayimprove customer satisfaction and retention.

In the discussion that follows, the electronic device may include aportable electronic device (such as a cellular telephone) or an accesspoint that communicates frames or packets in accordance with a wirelesscommunication protocol, such as an Institute of Electrical andElectronics Engineers (IEEE) 802.11 standard, Bluetooth, and/or anothertype of wireless interface. In the discussion that follows, Wi-Fi isused as an illustrative example. However, a wide variety ofcommunication protocols may be used, such as Long Term Evolution or LTE(from the 3rd Generation Partnership Project of Sophia Antipolis,Valbonne, France), LTE Advanced (or LTE-A), a third generation or 3Gcommunication protocol, a fourth generation or 4G communicationprotocol, a fifth generation or 5G communication protocol, or otherpresent or future developed advanced cellular communication protocol,etc.

Moreover, the access point may communicate with other access pointsand/or computers in a network using a wired communication protocol, suchas an IEEE 802.3 standard (which is sometimes referred to as ‘Ethernet’)and/or another type of wired interface. In the discussion that follows,Ethernet is used as an illustrative example.

FIG. 1 presents a block diagram illustrating an example of communicationamong one or more access points 110 and one or more electronic devices112 (such as a cellular telephone) in accordance with some embodiments.Notably, access points 110 may communicate with each other usingwireless and/or wired communication. Note that access points 110 mayinclude a physical access point and/or a virtual access point that isimplemented in software in an environment of an electronic device or acomputer. In addition, access points 110 may communicate with electronicdevices 112 using wireless communication.

The wired communication among access points 110 may occur via network114 (such as an intra-net, a mesh network, point-to-point connectionsand/or the Internet) and may use a network communication protocol, suchas Ethernet. Moreover, the wireless communication using Wi-Fi mayinvolve: transmitting advertising frames on wireless channels, detectingone another by scanning wireless channels, establishing connections (forexample, by transmitting association or attach requests), and/ortransmitting and receiving packets (which may include the associationrequests and/or additional information as payloads). In someembodiments, wireless communication among access points 110 alsoinvolves the use of dedicated connections, such as via a peer-to-peer(P2P) communication technique.

As described further below with reference to FIG. 9, access points 110and/or electronic devices 112 may include subsystems, such as anetworking subsystem, a memory subsystem and a processor subsystem. Inaddition, access points 110 and electronic devices 112 may includeradios 116 in the networking subsystems (which may include at least someof the functionality in an access-point module). More generally, accesspoints 110 and electronic devices 112 can include (or can be includedwithin) any electronic devices with the networking subsystems thatenable access points 110 and electronic devices 112 to communicate witheach other using wireless and/or wired communication. This wirelesscommunication can comprise transmitting advertisements on wirelesschannels to enable access points 110 and/or electronic devices 112 tomake initial contact or detect each other, followed by exchangingsubsequent data/management frames (such as association requests andresponses) to establish a connection, configure security options (e.g.,Internet Protocol Security), transmit and receive packets or frames viathe connection, etc. Note that while instances of radios 116 are shownin access points 110 and electronic devices 112, one or more of theseinstances may be different from the other instances of radios 116.

As can be seen in FIG. 1, wireless signals 118 (represented by a jaggedline) are transmitted from radio 116-1 in access point 110-1. Thesewireless signals may be received by radio 116-3 in electronic device112-1. In particular, access point 110-1 may transmit frames or packets.In turn, these frames or packets may be received by electronic device112-1. Moreover, access point 110-1 may allow electronic device 112-1 tocommunicate with other electronic devices, computers and/or servers vianetwork 114.

Note that the communication among access points 110 and/or withelectronic devices 112 may be characterized by a variety of performancemetrics, such as: a received signal strength (RSSI), a data rate, a datarate for successful communication (which is sometimes referred to as a‘throughput’), an error rate (such as a retry or resend rate), amean-square error of equalized signals relative to an equalizationtarget, intersymbol interference, multipath interference, asignal-to-noise ratio, a width of an eye pattern, a ratio of number ofbytes successfully communicated during a time interval (such as 1-10 s)to an estimated maximum number of bytes that can be communicated in thetime interval (the latter of which is sometimes referred to as the‘capacity’ of a communication channel or link), and/or a ratio of anactual data rate to an estimated data rate (which is sometimes referredto as ‘utilization’).

In the described embodiments, processing a packet or frame in accesspoints 110 and electronic devices 112 includes: receiving wirelesssignals 118 with the packet or frame; decoding/extracting the packet orframe from received wireless signals 118 to acquire the packet or frame;and processing the packet or frame to determine information contained inthe packet or frame.

Although we describe the network environment shown in FIG. 1 as anexample, in alternative embodiments, different numbers or types ofelectronic devices may be present. For example, some embodimentscomprise more or fewer electronic devices. As another example, inanother embodiment, different electronic devices are transmitting and/orreceiving packets or frames.

As described further below with reference to FIGS. 2-4 and 6-8, thecommunication technique may be performed by a given one of access points110 (such as access point 110-1) or a given one of electronic devices112 (such as electronic device 112-1). (Note that electronic devices 112are sometimes referred to as ‘clients,’ ‘stations’ or ‘recipientelectronic devices’ in WLAN 120.) Using access point 110-1 as anillustration, access point 110-1 may efficiently (e.g., with reducedcommunication overhead) and rapidly determine one or more antennapatterns. Notably, access point 110-1 may reserve N time slots in acommunication channel, such as, e.g., between 4 and 32 time slots. Forexample, the N time slots may be consecutive or adjacent time slots.Then, access point 110-1 may provide or transmit predefined packets orframes (such as NDPs) in the N time slots that are intended for or areto at least one of electronic devices (such as electronic device 112-1),where each time slot is associated with a different antenna pattern ofan antenna in or associated with access point 110-1. Moreover, accesspoint 110-1 may receive feedback (such as a feedback frame) associatedwith or from electronic device 112-1, where the feedback includesinformation specifying at least a time slot in the N time slots (such astime slot 3). For example, electronic device 112-1 may report theinformation for a time slot that has a maximum or largestsignal-to-noise ratio at electronic device 112-1 for the N time slotsand/or a particular angle of arrival. More generally, the informationfor the time slot may be reported based at least in part on aperformance metric. Next, access point 110-1 may select, based at leastin part on the feedback, an antenna pattern associated with the timeslot, such as the antenna pattern used when access point 110-1 providedor transmitted a predefined packet or frame in the time slot. Thisantenna pattern may be subsequently used by access point 110-1 whencommunicating with electronic device 112-1.

Moreover, in some embodiments, the information may specify a set ofranked time slots, such as time slot 4, time slot 1 and time slot 7. Forexample, the set of time slots may be ranked based at least in part onperformance metrics at electronic device 112-1 that is associated withthe N time slots, where a given performance metric for a given time slotmay include: a signal-to-noise ratio, an angle of arrival or both.

In some embodiments, access point 110-1 may provide or transmitpredefined packets or frames in the N time slots that are intended foror to two or more of electronic devices, such as electronic device 112-1and 112-2. In response, in addition to the feedback, access point 110-1may receive second feedback associated with or from electronic device112-2, where the second feedback comprises information specifying atleast a second time slot in the N time slots (such as time slot 2).Based at least in part on the second feedback, access point 110-1 mayselect a second antenna pattern associated with the second time slot,such as the second antenna pattern used when access point 110-1 providedor transmitted a predefined packet or frame in the second time slot.This second antenna pattern may be subsequently used by access point110-1 when communicating with electronic device 112-2. Note that thesecond antenna pattern may be the same as or different from the antennapattern.

Furthermore, in some embodiments, access point 110-1 may select, basedat least in part on the feedback and the second feedback, a commonantenna pattern for use when communicating jointly with electronicdevices 112-1 and 112-2. For example, the common antenna pattern may beused when providing or transmitting a group frame intended for or toelectronic devices 112-1 and 112-2.

Note that the feedback and the second feedback may include differentfeedback frames. Alternatively or additionally, the feedback and thesecond feedback may be conveyed in different sub-channels in a feedbackframe.

Furthermore, access point 110-1 may serially provide polling information(such as poll frames) intended for or to electronic device 112-1 andsecond polling information intended for or to electronic device 112-2.Alternatively, access point 110-1 may provide a trigger frame intendedfor or to electronic device 112-1 and 112-2, where the feedback and thesecond feedback are received concurrently in different sub-channels in afeedback frame.

In this way, the communication technique may allow access points 110and/or electronic devices 112 to determine one or more antenna patternsfor use when communication with each other. Consequently, thecommunication technique may provide improved communication performancewithout unnecessary overhead or time delay. Therefore, the communicationtechnique may improve the communication performance of access points 110and/or electronic devices 112, and may facilitate an improved userexperience when communicating information using access points 110 andelectronic devices 112.

We now describe embodiments of the method. FIG. 2 presents a flowdiagram illustrating an example of a method 200 for determining anantenna pattern, which may be performed by an electronic device, such asone of access points 110 or one of electronic devices 112 in FIG. 1.During operation, the electronic device may reserve N time slots(operation 210) in a communication channel. For example, the predefinedpackets or frames may include NDPs. Note that the N time slots may beconsecutive.

Then, the electronic device may provide predefined packets or frames inthe N time slots (operation 212) that are intended for at least thesecond electronic device, where each time slot is associated with adifferent antenna pattern of an antenna in or associated with theelectronic device. Note that the predefined packets or frames may bebroadband, such as, e.g., having a bandwidth of 20, 40 or 80 MHz.

Moreover, the electronic device may receive feedback (operation 214)associated with the second electronic device, where the feedbackincludes information specifying at least a time slot in the N timeslots. Furthermore, the time slot may have an extremum value of aperformance metric. For example, the performance metric may include asignal-to-noise ratio. Note that the feedback may include a feedbackframe.

Additionally, in some embodiments, the information may specify a set ofranked time slots. For example, the set of time slots may be rankedbased at least in part on performance metrics associated with the timeslots, where a given performance metric may include: a signal-to-noiseratio, an angle of arrival or both.

Next, the electronic device may select, based at least in part on thefeedback, the antenna pattern (operation 216) associated with the timeslot for use when communicating with the second electronic device.

In some embodiments, the electronic device optionally performs one ormore additional operations (operation 218). For example, the electronicdevice may wirelessly communicate with a third electronic device. Then,during operation, the electronic device may: receive second feedbackassociated with the third electronic device, where the second feedbackcomprises information specifying at least a second time slot in the Ntime slots; and select, based at least in part on the second feedback, asecond antenna pattern associated with the second time slot for use whencommunicating with the third electronic device.

Note that the feedback and the second feedback may include differentfeedback frames. Alternatively or additionally, the feedback and thesecond feedback may be conveyed in different sub-channels in a feedbackframe.

Furthermore, the electronic device may serially provide pollinginformation intended for the second electronic device and second pollinginformation intended for the third electronic device. Alternatively, theelectronic device may provide a trigger frame intended for the secondelectronic device and the third electronic device, where the feedbackand the second feedback are received concurrently in differentsub-channels in a feedback frame.

In some embodiments, the electronic device may select, based at least inpart on the feedback and the second feedback, a common antenna patternfor use when communicating jointly with the second electronic device andthe third electronic device.

Embodiments of the communication technique are further illustrated inFIG. 3, which presents a drawing illustrating communication among accesspoint 110-1 and electronic devices 112-1 and 112-2. Note that electronicdevices 112 may be communicatively attached or connected to access point110-1. For example, electronic devices 112 may be associated with accesspoint 110-1. In the discussion of FIG. 3, as an illustration, thecommunication technique is performed by access point 110-1.

During the communication technique, interface circuit (I.C.) 310 inaccess point 110-1 may provide a frame 312 to electronic device 112-1and/or 112-2 that reserves N time slots in a communication channel. Forexample, the frame 312 may be an antenna selection announcement orframe. Then, interface circuit 314 in electronic device 112-1 and/orinterface circuit 316 in electronic device 112-2 may receive frame 312.

Moreover, interface circuit 310 may predefined packets 318 (or frames)in the N time slots to electronic device 112-1 and/or 112-2, where eachtime slot is associated with a different antenna pattern of an antennain or associated with access point 110-1. Next, interface circuit 314and/or interface circuit 316 may receive predefined packets 318.

Furthermore, interface circuits 314 and/or 316 may, respectively,determine performance metrics 320 corresponding to predefined packets318. For example, performance metrics 320 may include one or more of:signal-to-noise ratios, angles of arrival, and/or another performancemetric associated with the communication of predefined packets 318.Based at least in part on performance metrics 320, interface circuits314 and/or 316 may, respectively, determine rankings 322 and/or 324 ofat least some of the time slots. For example, a given ranking may orderat least some of the time slots from the largest signal-to-noise ratio(or performance metric) to the smallest. Alternatively, a given rankingmay include at least a subset of the time slots having the top-M (whereM is an integer) signal-to-noise ratios (or performance metrics).

Additionally, interface circuits 314 and/or 316 may provide,respectively, feedback 328 and/or 332 to access point 110-1. Thefeedback from a given electronic device may include informationspecifying at least a time slot in the N time slots. More generally, theinformation may specify a given ranking of at least some of the N timeslots.

Note that feedback 328 and 332 may be included in separate feedbackframes. Alternatively, feedback 328 and 332 may be included in a commonfeedback frame, such as in different sub-channels in the common feedbackframe.

In some embodiments, interface circuit 310 optionally provide pollinginformation (such as polling frames 326 and/or 330) to electronicdevices 112-1 and/or 112-2 to request or solicit feedback 328 and/or332. In these embodiments, interface circuit 314 and/or 316 may providefeedback 328 and/or 332 in response to polling frames 326 and/or 330.Alternatively, in embodiments where feedback 328 and 332 are included ina common feedback frame, interface circuit 310 may request or solicitfeedback 328 and 332 by first providing a trigger frame (not shown) tointerface circuits 314 and 316.

After receiving feedback 328 and/or 332, interface circuit 310 may,respectively, select antenna patterns 334 and/or 336 to use whencommunicating with electronic devices 112-1 and/or 112-2 based at leastin part on feedback 328 and/or 332. Alternatively, in some embodiments,interface circuit 310 may select, based at least in part on feedback 328and 332, a common antenna pattern (not shown) for use when communicatingjointly with electronic devices 112-1 and 112-2. For example, the commonantenna pattern may be selected based at least in part on thehighest-ranked time slots that overlap or jointly occur in rankings 322and 324.

While FIG. 3 illustrates particular operations involving unilateral orbilateral communication, in general each of the operations illustratedin FIG. 3 may involve unilateral or bilateral communication.

FIG. 4 presents a timing diagram illustrating an example ofcommunication among access point 110-1 and electronic devices 112-1 and112-2. Notably, access point 110-1 may provide an antenna selectionannouncement 410 to reserve N time slots. Then, after a short interframespace (SIFS) 412, access point 110-1 may provide an antenna selectionframe 414 with predefined packets or frames (such as NDPs) in the N timeslots to electronic devices 112-1 and 112-2.

Next, after a SIFS 416, access point 110-1 may optionally provide apolling frame 418 to electronic device 112-1. In response, electronicdevice 112-1 may provide an antenna selection report 420 with feedback,including information that specifies at least one and, more generally, aranking of at least some of the time slots. As discussed previously,access point 110-1 may use this information to select an antenna patternto use when communicating with electronic device 112-1.

Furthermore, access point 110-1 may optionally provide a polling frame422 to electronic device 112-2. In response, electronic device 112-2 mayprovide an antenna selection report 424 with feedback, includinginformation that specifies at least one and, more generally, a rankingof at least some of the time slots. As discussed previously, accesspoint 110-1 may use this information to select an antenna pattern to usewhen communicating with electronic device 112-2.

In some embodiments of the communication technique, an access pointsends an antenna selection announcement. This antenna selectionannouncement may inform clients of the access point about an antennaselection frame. Notably, the antenna selection announcement may includea duration (such as a number time slots N) of the antenna selectionframe.

Then, following a SIFS, the access point may send the antenna selectionframe. This frame may include N NDP frames. Notably, for each time slot,a null data packet frame may be sent using a different antenna pattern.

When each client receives the whole antenna selection frame, it maycompare the signal-to-noise ratio of each time-slot, and may select orchoose one or more of the associated antenna patterns having the bestsignal-to-noise ratios. Next, the clients may store the time-slotnumbers corresponding to the selected antenna patterns. Note that theclients may receive the antenna selection frame using an omnidirectionalantenna pattern.

Moreover, after a SIFS, a first client may send an antenna selectionreport frame, which includes or reports the time-slot numbers selectedby the first client.

Furthermore, the access point may send an antenna selection report pollframe. In response, a second client may send an antenna selection reportframe, which includes or reports the time-slot numbers selected by thesecond client.

The operations of the access point sending an antenna selection reportpoll frame and a client responding with an antenna selection reportframe may be repeated for the remaining clients of the access point.

After the access point has received the antenna selection reportframe(s), the access point may know the antenna pattern(s) to use witheach client.

Note that the communication technique may be used with multi-usermultiple input multiple output (MU-MIMO) and/or orthogonalfrequency-division multiple access (OFDMA).

FIG. 5 presents a drawing illustrating an antenna pattern 500 of anantenna in access point 110-1. Alternatively, in some embodiments,antenna pattern 500 is of an antenna in one of electronic devices 112 inFIG. 1.

Notably, access point 110-1 may configure antenna elements in antenna510 to select a direction 514 of a primary beam 512 in antenna pattern500. This selective directionality may improve the sensitivity whenaccess point 110-1 transmits or receives a frame or a packet.

For example, an interface circuit in radio 116-1 may provide controlsignals or settings that adapt or change antenna pattern 500 of antenna510. In some embodiments, the control signals or settings mayindependently and selectively electrically couple pattern shapers orantenna elements (such as reflectors) in antenna 510 to ground in orderto steer antenna pattern 500 in different directions (such as direction514). Thus, if one or more antennas elements in antenna 510 include Nantenna pattern shapers, antenna 510 may have 2^(N) different antennapattern configurations. More generally, a given antenna pattern mayinclude amplitudes and/or phases of signals that specify a direction ofthe main or primary lobe or beam 512 of the given antenna pattern, aswell as so-called ‘exclusion regions’ or ‘exclusion zones’ (which aresometimes referred to as ‘notches’ or ‘nulls’). Note that an exclusionzone of the given antenna pattern includes a low-intensity region of thegiven antenna pattern. While the intensity is not necessarily zero inthe exclusion zone, it may be below a threshold, such as 3 dB or lowerthan the peak gain of the given antenna pattern. Thus, the given antennapattern may include a local maximum (e.g., a primary beam 512) thatdirects gain in direction 514 of, e.g., electronic device (E.D.) 112-1that is of interest and/or one or more local minima that reduce gain inthe direction of other electronic devices that are not of interest. Moregenerally, antenna pattern 500 may have N beams at locations ofelectronic devices (such as electronic device 112-1) that will transmitto or that will receive from access point 110-1 in the subsequent timeinterval and/or M exclusion zones at the locations of electronic devicesthat will not transmit to or receive from access point 110-1 in thesubsequent time interval, where N and M are integers. For example,antenna 510 may include M+1 antenna elements and there may be Mexclusion zones. In this way, the given antenna pattern may be selectedso that communication that is undesirable (such as with the otherelectronic devices) is avoided to reduce or eliminate adverse effects(such as interference or crosstalk) and to increase the sensitivity oftransmissions to or from electronic device 112-1.

In some embodiments, antenna pattern 500 is used when transmittingand/or receiving. While in some embodiments antenna pattern 500 may beomnidirectional, in other embodiments antenna pattern 500 may haveincreased directionality relative to an omnidirectional antenna pattern(e.g., a primary lobe or beam 512 of antenna pattern 500 may be directedso that the transmitted energy to or the received energy from, e.g.,electronic device 112-1 in increased, which may increase thecommunication performance (such as by improving one or more performancemetrics).

We now describe another embodiment of the communication technique. Theseembodiments may determine one or more antenna patterns using a very highthroughput (VHT) compressed beamforming report (specified in IEEE802.11ac and IEEE 802.11ax) with information that specifies thesignal-to-noise ratio, averaged over all subcarriers, of each space-timestream at a recipient electronic device, such as at one of electronicdevices 112 in FIG. 1. Thus, information determined during sounding maybe used to determine or select the one or more antenna patterns.

FIG. 6 presents a flow diagram illustrating an example of a method 600for determining an antenna pattern, which may be performed by anelectronic device, such as one of access points 110 or one of electronicdevices 112 in FIG. 1. During operation, the electronic device mayprovide a beamformer announcement (operation 610) intended for or to atleast a second electronic device. For example, the electronic device mayprovide an NDP announcement.

Then, the electronic device may provide a predefined packet or frameintended for or to a second electronic device using a first antennapattern (operation 612). For example, the predefined packet or frame mayinclude an NDP. Note that the predefined packet or frame may bebroadband, such as, e.g., having a bandwidth of 20, 40 or 80 MHz.

Moreover, the electronic device may receive a VHT compressed beamformingreport (operation 614) associated with or from the second electronicdevice. Note that the VHT compressed beamforming report may include oneor more performance metrics (such as the signal-to-noise ratio, theangle of arrival, etc.), averaged over all subcarrier, for eachspace-time stream at the second electronic device.

Next, the electronic device may repeat (operation 616) operations 612and 614 one or more times using one or more other or different antennapatterns.

Furthermore, the electronic device may select, based on the one or moreperformance metrics for each of the antenna patterns, an antenna pattern(operation 618) for use when communicating with the second electronicdevice (such as when transmitting and/or receiving).

In some embodiments, the electronic device may optionally perform one ormore additional operations (operation 620). For example, in embodimentsin which multi-user beamforming is performed, the electronic device mayalso provide the beamformer announcement (operation 610) and thepredefined packet or frame (operation 612) to, e.g., at least a thirdelectronic device. Then, after the electronic device receives the VHTcompressed beamforming report (operation 614) associated with or fromthe second electronic device, the electronic device may: provide a pollframe (such as a beamforming report poll or BRP frame) to the thirdelectronic device; and receive a VHT compressed beamforming reportassociated with or from the third electronic device. Next, instead ofselecting the antenna pattern (operation 618) for use with the secondelectronic device, the electronic device may use the performance metricsin the VHT compressed beamforming reports to select a common antennapattern for use when communicating with the second electronic device andthe third antenna pattern.

While the preceding discussion illustrated method 600 using serialpolling recipient electronic devices, in other embodiments VHTcompressed beamforming reports may be provided concurrently. Forexample, the electronic device may provide a trigger frame, and therecipient electronic devices may provide the VHT compressed beamformingreports in different sub-channels in a common frame.

In some embodiments of methods 200 (FIG. 2) and/or 600, there may beadditional or fewer operations. Moreover, there may be one or moredifferent operations. Furthermore, the order of the operations may bechanged, and/or two or more operations may be combined into a singleoperation.

Embodiments of the communication technique are further illustrated inFIG. 7, which presents a drawing illustrating communication among accesspoint 110-1 and electronic device 112-1. Note that electronic device112-1 may be communicatively attached or connected to access point110-1. For example, electronic device 112-1 may be associated withaccess point 110-1. In the discussion of FIG. 7, as an illustration, thecommunication technique is performed by access point 110-1.

During the communication technique, interface circuit (I.C.) 710 inaccess point 110-1 may provide a beamformer announcement (BA) 712-1 toelectronic device 112-1. This beamformer announcement 712-1 may bereceived by interface circuit 714 in electronic device 112-1.

Then, interface circuit 710 may provide a predefined packet or frame716-1 to electronic device 112-1 using a first antenna pattern. Afterreceiving the predefined packet or frame 716-1, interface circuit 714may determine a VHT compressed beamforming report 718-1. Moreover,interface circuit 714 may provide the VHT compressed beamforming report718-1 to access point 110-1.

Next, interface circuit 710 may repeat, one or more times, providinginstances of the beamformer announcement (BA) 712 and providinginstances of the predefined packet or frame 716 using different antennapatterns. In response, interface circuit 714 may determine instances ofassociated VHT compressed beamforming reports 718, and may provide theseVHT compressed beamforming reports 718 to access point 110-1.

After receiving the VHT compressed beamforming reports 718, interfacecircuit 710 may select, based on the one or more performance metrics foreach of the antenna patterns included in the VHT compressed beamformingreports, an antenna pattern 720 for use when communicating withelectronic device 112-1.

While FIG. 7 illustrates particular operations involving unilateral orbilateral communication, in general each of the operations illustratedin FIG. 7 may involve unilateral or bilateral communication.

FIG. 8 presents a timing diagram illustrating an example ofcommunication among access point 110-1 and electronic device 112-1.Notably, access point 110-1 may provide an NDP announcement (NDPA)810-1. Then, access point 110-1 may provide an NDP 812-1 using a firstantenna pattern.

Moreover, after determining a VHT compressed beamforming report 814-1 inresponse to receiving NDP 812-1, electronic device 112-1 may provide theVHT compressed beamforming report 814-1 to access point 110-1.

Next, access point 110-1 may repeat, one or more times, providinginstances of NDP announcements 810 and providing instances of NDP 812using different antenna patterns, and electronic device 112-1 maydetermine and provide instances of associated VHT compressed beamformingreports 814 to access point 110-1. For example, access point 110-1 mayprovide an NDP announcement 810-2 and may provide an NDP 812-2 using asecond antenna pattern. In response to receiving NDP 812-2, electronicdevice 112-1 may determine a VHT compressed beamforming report 814-2 andmay provide the VHT compressed beamforming report 814-2 to access point110-1.

As discussed previously, access point 110-1 may use theperformance-metric information in VHT compressed beamforming reports 814to select an antenna pattern to use when communicating with electronicdevice 112-1.

In some embodiments of the communication technique, signal-to-noiseinformation in VHT compressed beamforming reports is used to select anantenna pattern for use when communicating with an electronic device.Notably, during single-user beamforming, an access point (and, moregenerally, a beamformer) may send an NDP announcement. Then, the accesspoint may send an NDP using a first antenna pattern. In response, anelectronic device (and, more generally, a beamformee) may determine andmay send a VHT Compressed Beamforming Report to the access point. Theaccess point may repeat, one or more times, sending NDPs using differentantenna patterns, and the electronic device may respond by determiningand sending associated VHT Compressed Beamforming Report to the accesspoint. Using the performance-metric information in the VHT CompressedBeamforming Reports, the access point may select an antenna pattern touse when communicating with the electronic device. For example, theselected antenna pattern may have a maximum or largest signal-to-noiseratio in the VHT Compressed Beamforming Reports.

Alternatively, during multi-user beamforming, an access point (and, moregenerally, a beamformer) may send an NDP announcement. Then, the accesspoint may send an NDP using a first antenna pattern. In response, afirst electronic device (and, more generally, a beamformee) maydetermine and may send a VHT Compressed Beamforming Report to the accesspoint. Moreover, the access point may send a BRP frame to a secondelectronic device. In response, the second electronic device (and, moregenerally, a second beamformee) may determine and may send a second VHTCompressed Beamforming Report to the access point. Next, the accesspoint may send a BRP frame to a third electronic device. In response,the third electronic device (and, more generally, a third beamformee)may determine and may send a third VHT Compressed Beamforming Report tothe access point. The polling and reporting operations may be repeateduntil all the electronic devices have reported. Furthermore, thepreceding operations may be repeated one or more times for differentantenna patterns. Using the performance-metric information in the VHTCompressed Beamforming Reports, the access point may select an antennapattern to use when communicating with the electronic devices, such asduring multi-user beamforming. For example, the selected antenna patternmay have a maximum or largest average or mean signal-to-noise ratio inthe VHT Compressed Beamforming Reports.

We now describe embodiments of an electronic device, which may performat least some of the operations in the communication technique. Forexample, the electronic device may include one of access points 110 orelectronic devices 112 in FIG. 1. FIG. 9 presents a block diagramillustrating an electronic device 900 in accordance with someembodiments. This electronic device includes processing subsystem 910,memory subsystem 912, and networking subsystem 914. Processing subsystem910 includes one or more devices configured to perform computationaloperations. For example, processing subsystem 910 can include one ormore microprocessors, ASICs, microcontrollers, programmable-logicdevices, graphics processing units (GPUs) and/or one or more digitalsignal processors (DSPs).

Memory subsystem 912 includes one or more devices for storing dataand/or instructions for processing subsystem 910 and networkingsubsystem 914. For example, memory subsystem 912 can include dynamicrandom access memory (DRAM), static random access memory (SRAM), and/orother types of memory. In some embodiments, instructions for processingsubsystem 910 in memory subsystem 912 include: one or more programmodules or sets of instructions (such as program instructions 922 oroperating system 924), which may be executed by processing subsystem910. Note that the one or more computer programs may constitute acomputer-program mechanism. Moreover, instructions in the variousmodules in memory subsystem 912 may be implemented in: a high-levelprocedural language, an object-oriented programming language, and/or inan assembly or machine language. Furthermore, the programming languagemay be compiled or interpreted, e.g., configurable or configured (whichmay be used interchangeably in this discussion), to be executed byprocessing subsystem 910.

In addition, memory subsystem 912 can include mechanisms for controllingaccess to the memory. In some embodiments, memory subsystem 912 includesa memory hierarchy that comprises one or more caches coupled to a memoryin electronic device 900. In some of these embodiments, one or more ofthe caches is located in processing subsystem 910.

In some embodiments, memory subsystem 912 is coupled to one or morehigh-capacity mass-storage devices (not shown). For example, memorysubsystem 912 can be coupled to a magnetic or optical drive, asolid-state drive, or another type of mass-storage device. In theseembodiments, memory subsystem 912 can be used by electronic device 900as fast-access storage for often-used data, while the mass-storagedevice is used to store less frequently used data.

Networking subsystem 914 includes one or more devices configured tocouple to and communicate on a wired and/or wireless network (i.e., toperform network operations), including: control logic 916, an interfacecircuit 918 and one or more antennas 920 (or antenna elements). (WhileFIG. 9 includes one or more antennas 920, in some embodiments electronicdevice 900 includes one or more nodes, such as nodes 908, e.g., a pad,which can be coupled to the one or more antennas 920. Thus, electronicdevice 900 may or may not include the one or more antennas 920. Notethat nodes 908 may include one or more input nodes and/or one or moreoutput nodes.) For example, networking subsystem 914 can include aBluetooth™ networking system, a cellular networking system (e.g., a3G/4G/5G network such as UMTS, LTE, etc.), a universal serial bus (USB)networking system, a networking system based on the standards describedin IEEE 802.11 (e.g., a Wi-Fi networking system), an Ethernet networkingsystem, and/or another networking system.

Note that a transmit or receive antenna pattern (or antenna radiationpattern) of electronic device 900 may be adapted or changed usingpattern shapers (such as reflectors) in one or more antennas 920 (orantenna elements), which can be independently and selectivelyelectrically coupled to ground to steer the transmit antenna pattern indifferent directions. Thus, if one or more antennas 920 include Nantenna pattern shapers, the one or more antennas may have 2^(N)different antenna pattern configurations. More generally, a givenantenna pattern may include amplitudes and/or phases of signals thatspecify a direction of the main or primary lobe of the given antennapattern, as well as so-called ‘exclusion regions’ or ‘exclusion zones’(which are sometimes referred to as ‘notches’ or ‘nulls’). Note that anexclusion zone of the given antenna pattern includes a low-intensityregion of the given antenna pattern. While the intensity is notnecessarily zero in the exclusion zone, it may be below a threshold,such as 3 dB or lower than the peak gain of the given antenna pattern.Thus, the given antenna pattern may include a local maximum (e.g., aprimary beam) that directs gain in the direction of electronic device900 that is of interest, and one or more local minima that reduce gainin the direction of other electronic devices that are not of interest.In this way, the given antenna pattern may be selected so thatcommunication that is undesirable (such as with the other electronicdevices) is avoided to reduce or eliminate adverse effects, such asinterference or crosstalk.

Networking subsystem 914 includes processors, controllers,radios/antennas, sockets/plugs, and/or other devices used for couplingto, communicating on, and handling data and events for each supportednetworking system. Note that mechanisms used for coupling to,communicating on, and handling data and events on the network for eachnetwork system are sometimes collectively referred to as a ‘networkinterface’ for the network system. Moreover, in some embodiments a‘network’ or a ‘connection’ between the electronic devices does not yetexist. Therefore, electronic device 900 may use the mechanisms innetworking subsystem 914 for performing simple wireless communicationbetween the electronic devices, e.g., transmitting advertising or beaconframes and/or scanning for advertising frames transmitted by otherelectronic devices as described previously.

Within electronic device 900, processing subsystem 910, memory subsystem912, and networking subsystem 914 are coupled together using bus 928.Bus 928 may include an electrical, optical, and/or electro-opticalconnection that the subsystems can use to communicate commands and dataamong one another. Although only one bus 928 is shown for clarity,different embodiments can include a different number or configuration ofelectrical, optical, and/or electro-optical connections among thesubsystems.

In some embodiments, electronic device 900 includes a display subsystem926 for displaying information on a display, which may include a displaydriver and the display, such as a liquid-crystal display, a multi-touchtouchscreen, etc.

Electronic device 900 can be (or can be included in) any electronicdevice with at least one network interface. For example, electronicdevice 900 can be (or can be included in): a desktop computer, a laptopcomputer, a subnotebook/netbook, a server, a tablet computer, asmartphone, a cellular telephone, a smartwatch, a consumer-electronicdevice, a portable computing device, a wearable device, an access point,a transceiver, an eNodeB, a router, a switch, communication equipment, acontroller, test equipment, and/or another electronic device.

Although specific components are used to describe electronic device 900,in alternative embodiments, different components and/or subsystems maybe present in electronic device 900. For example, electronic device 900may include one or more additional processing subsystems, memorysubsystems, networking subsystems, and/or display subsystems.Additionally, one or more of the subsystems may not be present inelectronic device 900. Moreover, in some embodiments, electronic device900 may include one or more additional subsystems that are not shown inFIG. 9. Also, although separate subsystems are shown in FIG. 9, in someembodiments some or all of a given subsystem or component can beintegrated into one or more of the other subsystems or component(s) inelectronic device 900. For example, in some embodiments programinstructions 922 are included in operating system 924 and/or controllogic 916 is included in interface circuit 918.

Moreover, the circuits and components in electronic device 900 may beimplemented using any combination of analog and/or digital circuitry,including: bipolar, PMOS and/or NMOS gates or transistors. Furthermore,signals in these embodiments may include digital signals that haveapproximately discrete values and/or analog signals that have continuousvalues. Additionally, components and circuits may be single-ended ordifferential, and power supplies may be unipolar or bipolar.

An integrated circuit (which is sometimes referred to as a‘communication circuit’) may implement some or all of the functionalityof networking subsystem 914. The integrated circuit may include hardwareand/or software mechanisms that are used for transmitting wirelesssignals from electronic device 900 and receiving signals at electronicdevice 900 from other electronic devices. Aside from the mechanismsherein described, radios are generally known in the art and hence arenot described in detail. In general, networking subsystem 914 and/or theintegrated circuit can include any number of radios. Note that theradios in multiple-radio embodiments function in a similar way to thedescribed single-radio embodiments.

In some embodiments, networking subsystem 914 and/or the integratedcircuit include a configuration mechanism (such as one or more hardwareand/or software mechanisms) that configures the radio(s) to transmitand/or receive on a given communication channel (e.g., a given carrierfrequency). For example, in some embodiments, the configurationmechanism can be used to switch the radio from monitoring and/ortransmitting on a given communication channel to monitoring and/ortransmitting on a different communication channel. (Note that‘monitoring’ as used herein comprises receiving signals from otherelectronic devices and possibly performing one or more processingoperations on the received signals)

In some embodiments, an output of a process for designing the integratedcircuit, or a portion of the integrated circuit, which includes one ormore of the circuits described herein may be a computer-readable mediumsuch as, for example, a magnetic tape or an optical or magnetic disk.The computer-readable medium may be encoded with data structures orother information describing circuitry that may be physicallyinstantiated as the integrated circuit or the portion of the integratedcircuit. Although various formats may be used for such encoding, thesedata structures are commonly written in: Caltech Intermediate Format(CIF), Calma GDS II Stream Format (GDSII) or Electronic DesignInterchange Format (EDIF). Those of skill in the art of integratedcircuit design can develop such data structures from schematics of thetype detailed above and the corresponding descriptions and encode thedata structures on the computer-readable medium. Those of skill in theart of integrated circuit fabrication can use such encoded data tofabricate integrated circuits that include one or more of the circuitsdescribed herein.

While the preceding discussion used a Wi-Fi communication protocol as anillustrative example, in other embodiments a wide variety ofcommunication protocols and, more generally, wireless communicationtechniques may be used. Thus, the communication technique may be used ina variety of network interfaces. Furthermore, while some of theoperations in the preceding embodiments were implemented in hardware orsoftware, in general the operations in the preceding embodiments can beimplemented in a wide variety of configurations and architectures.Therefore, some or all of the operations in the preceding embodimentsmay be performed in hardware, in software or both. For example, at leastsome of the operations in the communication technique may be implementedusing program instructions 922, operating system 924 (such as a driverfor interface circuit 918) or in firmware in interface circuit 918.Alternatively or additionally, at least some of the operations in thecommunication technique may be implemented in a physical layer, such ashardware in interface circuit 918.

In the preceding description, we refer to ‘some embodiments.’ Note that‘some embodiments’ describes a subset of all of the possibleembodiments, but does not always specify the same subset of embodiments.Moreover, note that numerical values in the preceding embodiments areillustrative examples of some embodiments. In other embodiments of thecommunication techniques, different numerical values may be used.

While the preceding discussion illustrated the communication techniquesusing communication in one or more particular bands of frequencies, oneor more other bands of frequencies may be used, such as bands offrequencies corresponding to Wi-Fi, LTE and/or Citizens Broadband RadioService (CBRS). For example, the bands of frequencies may include: aband of frequencies between 3.55 and 3.7 GHz, a band of frequencies nearor including 2.4 GHz, a band of frequencies near or including 3.6 GHz, aband of frequencies near or including 4.9 GHz, a band of frequenciesnear or including 5 GHz, a band of frequencies near or including 5.9 GHzor 6 GHz, a band of frequencies near 60 GHz and/or another band offrequencies. Note that the bands of frequencies may include one or morebands of frequencies.

The foregoing description is intended to enable any person skilled inthe art to make and use the disclosure, and is provided in the contextof a particular application and its requirements. Moreover, theforegoing descriptions of embodiments of the present disclosure havebeen presented for purposes of illustration and description only. Theyare not intended to be exhaustive or to limit the present disclosure tothe forms disclosed. Accordingly, many modifications and variations willbe apparent to practitioners skilled in the art, and the generalprinciples defined herein may be applied to other embodiments andapplications without departing from the spirit and scope of the presentdisclosure. Additionally, the discussion of the preceding embodiments isnot intended to limit the present disclosure. Thus, the presentdisclosure is not intended to be limited to the embodiments shown, butis to be accorded the widest scope consistent with the principles andfeatures disclosed herein.

What is claimed is:
 1. An electronic device, comprising: an antenna; andan interface circuit, coupled to the antenna, configured to wirelesslycommunicate with a second electronic device, wherein the electronicdevice is configured to perform operations comprising: provide, from theinterface circuit, a beamformer announcement addressed to the secondelectronic device; provide, from the interface circuit and using a firstantenna pattern, an instance of a predefined frame addressed to thesecond electronic device; receive, at the interface circuit, an instanceof a beamforming report associated with the second electronic device,wherein the instance of the beamforming report comprises one or moreperformance metrics averaged over multiple subcarriers in a band offrequencies, wherein a given performance metric is associated with agiven space-time stream at the second electronic device; repeat, one ormore times, the providing of the instance of the predefined frameaddressed to the second electronic device and the receiving of theinstance of the beamforming report associated with the second electronicdevice, wherein a given repeat of the providing of the instance of thebeamforming report uses a different antenna pattern than the firstantenna pattern or in other repeats of the providing of the instance ofthe beamforming report addressed to the second electronic device; andselect, based at least in part on one or more instances of thebeamforming report for different antenna patterns, a second antennapattern for use when communicating with the second electronic device. 2.The electronic device of claim 1, wherein the beamformer announcementcomprises a null data packet (NDP) announcement.
 3. The electronicdevice of claim 1, wherein the instance of the predefined frame has abandwidth that encompasses the multiple subcarriers in the band offrequencies.
 4. The electronic device of claim 1, wherein the instanceof the beamforming report comprises a very high throughput (VHT)compressed beamforming report.
 5. The electronic device of claim 1,wherein the one or more performance metrics comprise: a signal-to-noiseratio, or an angle of arrival.
 6. The electronic device of claim 1,wherein the second antenna pattern is used when transmitting a firstpacket or frame addressed to the second electronic device, receiving asecond packet or frame associated with the second electronic device, orboth.
 7. The electronic device of claim 1, wherein the instance of thepredefined frame comprises a null data packet (NDP).
 8. The electronicdevice of claim 1, wherein the interface circuit is configured towirelessly communicate with a third electronic device; and wherein theelectronic device is configured to: provide, from the interface circuit,the beamformer announcement addressed to the third electronic device;provide, from the interface circuit and using the first antenna pattern,the instance of the predefined frame addressed to the third electronicdevice; receive, at the interface circuit, the instance of thebeamforming report associated with the third electronic device, whereinthe instance of the beamforming report comprises one or more performancemetrics averaged over the multiple subcarriers in the band offrequencies, wherein the given performance metric is associated with thegiven space-time stream at the third electronic device; and repeat, oneor more times, the providing of the instance of the predefined frameaddressed to the third electronic device and the receiving of theinstance of the beamforming report associated with the third electronicdevice, wherein the given repeat of the providing of the instance of thebeamforming report uses the different antenna pattern than the firstantenna pattern or in the other repeats of the providing of the instanceof the beamforming report addressed to the third electronic device. 9.The electronic device of claim 8, wherein the instances of the beamformreport associated with the second electronic device are included indifferent frames than the instances of the beamform report associatedwith the third electronic device.
 10. The electronic device of claim 8,wherein at least one of the instances of the beamform report associatedwith the second electronic device and at least one of the instances ofthe beamform report associated with the third electronic device areconveyed in different sub-channels in a feedback frame.
 11. Theelectronic device of claim 8, wherein the electronic device isconfigured to serially provide, from the interface circuit, pollinginformation intended for the second electronic device and second pollinginformation intended for the third electronic device; and wherein theinstances of the beamform report associated with the second electronicdevice are in response to the polling information and the instances ofthe beamform report associated with the third electronic device are inresponse to the second polling information.
 12. The electronic device ofclaim 8, wherein the electronic device is configured to provide, fromthe interface circuit, a trigger frame intended for the secondelectronic device and the third electronic device; and wherein at leastone of the instances of the beamform report associated with the secondelectronic device and at least one of the instances of the beamformreport associated with the third electronic device are receivedconcurrently in different sub-channels in a feedback frame and inresponse to the trigger frame.
 13. The electronic device of claim 8,wherein the electronic device is configured to select, based at least inpart on the instances of the beamforming report for the differentantenna patterns and associated with the second electronic device andthe instances of the beamforming report for the different antennapatterns and associated with the third electronic device, a commonantenna pattern for use when communicating jointly with the secondelectronic device and the third electronic device.
 14. A non-transitorycomputer-readable storage medium for use in conjunction with anelectronic device, the computer-readable storage medium storing programinstructions, wherein, when executed by the electronic device, theprogram instructions cause the electronic device to perform operationscomprising: providing, from an interface circuit, a beamformerannouncement addressed to a second electronic device; providing, fromthe interface circuit and using a first antenna pattern, an instance ofa predefined frame addressed to the second electronic device; receiving,at the interface circuit, an instance of a beamforming report associatedwith the second electronic device, wherein the instance of thebeamforming report comprises one or more performance metrics averagedover multiple subcarriers in a band of frequencies, wherein a givenperformance metric is associated with a given space-time stream at thesecond electronic device; repeating, one or more times, the providing ofthe instance of the predefined frame addressed to the second electronicdevice and the receiving of the instance of the beamforming reportassociated with the second electronic device, wherein a given repeat ofthe providing of the instance of the beamforming report uses a differentantenna pattern than the first antenna pattern or in other repeats ofthe providing of the instance of the beamforming report addressed to thesecond electronic device; and selecting, based at least in part on oneor more instances of the beamforming report for different antennapatterns, a second antenna pattern for use when communicating with thesecond electronic device.
 15. The non-transitory computer-readablestorage medium of claim 14, wherein the beamformer announcementcomprises a null data packet (NDP) announcement.
 16. The non-transitorycomputer-readable storage medium of claim 14, wherein the instance ofthe beamforming report comprises a very high throughput (VHT) compressedbeamforming report.
 17. The non-transitory computer-readable storagemedium of claim 14, wherein the operations comprise: providing, from theinterface circuit, the beamformer announcement addressed to the thirdelectronic device; providing, from the interface circuit and using thefirst antenna pattern, the instance of the predefined frame addressed tothe third electronic device; receiving, at the interface circuit, theinstance of the beamforming report associated with the third electronicdevice, wherein the instance of the beamforming report comprises one ormore performance metrics averaged over the multiple subcarriers in theband of frequencies, wherein the given performance metric is associatedwith the given space-time stream at the third electronic device; andrepeating, one or more times, the providing of the instance of thepredefined frame addressed to the third electronic device and thereceiving of the instance of the beamforming report associated with thethird electronic device, wherein the given repeat of the providing ofthe instance of the beamforming report uses the different antennapattern than the first antenna pattern or in the other repeats of theproviding of the instance of the beamforming report addressed to thethird electronic device.
 18. The non-transitory computer-readablestorage medium of claim 14, wherein the instances of the beamform reportassociated with the second electronic device are included in differentframes than the instances of the beamform report associated with thethird electronic device.
 19. The non-transitory computer-readablestorage medium of claim 14, wherein at least one of the instances of thebeamform report associated with the second electronic device and atleast one of the instances of the beamform report associated with thethird electronic device are conveyed in different sub-channels in afeedback frame.
 20. A method for selecting a second antenna pattern,comprising: by an electronic device: providing, from an interfacecircuit, a beamformer announcement addressed to a second electronicdevice; providing, from the interface circuit and using a first antennapattern, an instance of a predefined frame addressed to the secondelectronic device; receiving, at the interface circuit, an instance of abeamforming report associated with the second electronic device, whereinthe instance of the beamforming report comprises one or more performancemetrics averaged over multiple subcarriers in a band of frequencies,wherein a given performance metric is associated with a given space-timestream at the second electronic device; repeating, one or more times,the providing of the instance of the predefined frame addressed to thesecond electronic device and the receiving of the instance of thebeamforming report associated with the second electronic device, whereina given repeat of the providing of the instance of the beamformingreport uses a different antenna pattern than the first antenna patternor in other repeats of the providing of the instance of the beamformingreport addressed to the second electronic device; and selecting, basedat least in part on one or more instances of the beamforming report fordifferent antenna patterns, a second antenna pattern for use whencommunicating with the second electronic device.